Multistage process for electrical dehydration of emulsions



July 6 1926. 1,591,472

J. H. C. DE BREY MULTISTAGE PROCESS FOR ELECTRICAL DEHYDRATION OFEMUBSIONS Filed March 26, 1925 15101270507 J O de Bray Patented July 6,1926.

1,591,472 PATENT OFFICE.

JAN-HEINRICII CHBISTOPH mi BBEY, Oil? THE HAGUE, NETHERLANDS.

llIUIrTISTAGE PROCESS FOR ELECTRICAL DEHYDBATION OF EMULSIONS.

Application filed March 26, 1925. Serial no. 18,610.

My invention relates to an improvement for separating the phases of anemulsion especially of mineral oil by means of electric current. It iswell sions generally consist of a multitude of Water globules of varioussizes dispersed in a medium'of oil. The size of these water globulesvaries widely from 0.1 micron up to one millimeter in diameter, andusually one and the same emulsion contains globules of the most widelyvarying diameter.

Hitherto it has been the object of the ex- I 'isting processes forelectric dehydration to separate all the water globules, the smallest aswell as the largest, simultaneously from the oil, i. e. under the sameelectro-physical conditions. In those cases where the proc-. ess ofdehydration has been carried out in consecutive steps it hasnevertheless been customary to apply the. same electric ressure for theconsecutive steps. It is, owever, obvious that this is not the rightprinciple, as it is self-evident that it requires 0t er physical, thatis, electrical, conditions for segregating lobules of, say 1 millimeterdiameter than I ecopic particles of one micron diameter and ess.- thewater particles are, the higher the electric pressure required tosegregate them from the oil. Consequently, in order to obtain a completedehydration of an emulsion,

i. e. not only the segregation of the comparatively larger globules butalso of the smallest water particles, an electric pressure of 10.000 to50.000 volts is required.

The application of these high electric pressures to emulsions of highwater content meets with difliculties on account of the low electricresistance of these emulsions, which ractically cause an electricalshort-circuit or the-high voltages. I have found a method whereby thesedifiiculties are obviated and which consists therein that the emulsionis being treated in steps at con"- secutive higher pressures, wherebyduring each step' rior to applying the next hi her pressuret e waterfreed by the preceding lower pressure step, is separated from theemulsion.

I can carry out my process in a periodical manner but I prefer toproceed continuously.

T e process can best be elucidated by the following-example, in which anumber ofcontainers are referred to, although accordknown that emulorsegregating the micro- In fact I have found that the smaller ing to myinvention the process may be carried out in only one container.

The emulsion containers (a, b, c, d and e) each of which is equippedwith an electrode 1 of suitable desigmzare put in cascade, as shownon-the accompanying sketch.

As illustrated in said sketch one end of the secondary of a transformeris connected to the electrode and the other end to the wall of thecontainer.

, The emulsion, which contains 40% water, enters the first container(1," preferably at the bottom through the pipe 2 with cock 3. In thisfirst container (1 the emulsion is exposed to an electric pressure .of500- to 1000 volts. The larger water particles segregate easily underthe influence of these low pressures, but the smaller particles remainuntouched. The water, which is drained off continually from the bottomof container a through the pipe 1 will amount to about 75% of the totalwater content of the emulsion. Thus the water content of the e1nulsionat the top of this first container a will be about 14%. This 14%emulsion, which on account of its lower water content has a considerablyhigher electric resistance than to a considerably higher electric tainera. flows preferably by gravity (but naturally it can also be pumped, ifnecessary) to a second container 6, where again it enters preferably atthe bottom and where under the influence, of the electric pressure of5000 to 10.000 volts it will again lose about of its water. This wateris again drained ofi at the bottom, and the top of the emulsioncontainer 6 will show a water percentage of about 4%.

Looking through the miscrosoope it can now be observed that all thelarger water particles have disappeared and that the emulsion containsmerely water globules of a diameter of 20 microns and less. Thisemulsion can now be. exposed to a higher electric pressure and this iseifected in a.

third container 0, where the process is rerunning respectively at 30.000and 50.000

' cordance with its decreasing water content.

The process can be carried out with ordmary smusoidal alternate current,as also with the so-called pulsating alternate current, which is theobject of my invention as described in my application for Letters PatentSerial No. 705958 filed April 11, 1924.

I claim:

1. A process for separating the phases of emulsions by means of theelectric current, consisting in subjecting the emulsion to a multi-stagedehydrating process under successively higher electric pressures.

2. The process of separating the phases of emulsions by means of theelectric our.- rent, consisting in subjecting the emulsion to amulti-stage dehydrating process with successively higher electricpressures in each successive dehydrating stage, the electric pressuresincreasing in accordance with the decreasing Water content of theemulsion.

3. The process of separating the phases of emulsions by means of theelectric current, consisting in subjecting the emulsion to a multi-stagedehydrating process with successively higher electric pressures in eachsuccessive dehydrating stage, the electric pressures increasing inaccordance with the decreasing water content of the emulsion, theseparating water content being drained of? at each stage.

4. The process of dehydrating mineral oil emulsions, consisting insubjecting the emulsions in successive stages to relatively increaseelectric pressures and physically eliminating the Water separated fromthe emulsion at each stage.

5. An electric dehydrating process for mineral oil emulsions, consistingin the utilization of the electric current at successively higherelectric pressures for treating the emulsion in successive stages, thewater separated by the treatment bein divided from the emulsionfollowing eac stage treatment.

In testimony whereof I afiix my signature.

JAN HEINRICH CHMS'E'UPH ale BREY.

